Site frequencies in an alignment

So, here's one reason for the Scrapbook. You say, "why write something I already sort of wrote?" So today I came to the Scrapbook to cannibalize Site entropy in an alignment, to get it to squirt out the actual frequencies of each nucleotide at each site. The key here is the round-trip: a new scrap for you, based on the mods. --Ed.

To get an array of hashes of hashes containing the frequencies of each residue at each site of an alignment: